Ultrium 448 not compressing, keeps turning compression off

[mmcclure]

I'm rusty on tape drives so I might be missing something obvious here.  I have an Ultrium 448 external SCSI drive and Bakcup Exe 2012.  BE was saying the tape was filling everynight all of a sudden, I check Library & Tape Tools and it says hardware compression is disabled.  I enable it, let a job run, next day it's filling the tape again, L&TT says compression is off again.  BE is set to use hardware compression only.  I have a ticket open with Symantec, not sure at this point if the issue is with the drive or BE.   Thanks in advance for any input.

[TarunJain]

Should be Backup Exec. Did anything changed before this issue appeared? Are you trying to compress already compressed file types (jpg, mp3 etc.), BE might be turning off compression if nothing could be compressed.